<?php
/**
 * Ecma-262 5rd A.1 Lexical Grammar
 * 
 * 其中定义两种输入元素(InputElement):
 *     1. InputElementDiv
 *     2. InputElementRegExp
 * 
 * 但是由于lexcical analysis阶段无法区分是div还是reg
 * 因此为了简化drift-engine,暂时不考虑正则
 * 只考虑InputElementDiv
 * 
 *
 */
class InputElement {
    
    const Unknown = 0;
    const WhiteSpace = 1;
    const LineTerminator = 2;
    const Comment = 3;
    const Token = 4;
    
    /**
     * 
     * @var int
     */
    public $inputElementType;
    
    
    function __construct(){
        $this->inputElementType = InputElement::Unknown;
    }
}